Preliminary study on the effects of high magnitude, low frequency of whole body vibration in physical activity of osteoporotic women

Aim. Osteoporosis is nowadays affecting a large population. Recent studies, performed on animals and human beings, have shown that high magnitude, low frequency mechanical stimuli produce anabolic effects on bone tissue, increasing both bone density and strength. Aim of this study is to verify the effects of whole body vibration on bone tissue of trained osteoporotic women underwent to high magnitude and low-frequency vibration exercise on a vibrating platform. Methods. Twenty-six osteoporotic women, trained with low impact exercise regimen, voluntarily participated in the study and were randomly divided in two group: experimental (E) and control (C). All subjects weren't to any pharmacological therapy. The T-score, Ultrasound Bone Profile Index (UPBI) was calculated using them Amplitude-Dependent Speed of Sound (AD-SoS) measured with QUS. Results. Thirteen osteoporotic women following four months of ten-minute treatments, three per week, of high magnitude (3.0 g) and low frequency (30Hz) mechanical vibration improved the Amplitude-Dependent Speed of Sound (AD-SoS) QUS parameter from 1878.67+/-79.45 to 1971.17+/-78.69 m/s (P<0.002). The T-score in the experimental group shows an inversion trend passing from -3.50+/-1.13 to -2.18+/-1.12 (P<0.002) and the Ultrasound Bone Profile Index (UPBI) improves from 0.34+/-0.11 to 0.47+/-0.21 (P<0.01). In the control group (low impact exercise) any of these parameters considered shows significantly changes over the same period of time. Conclusion. Given that these accelerations were well tolerated by the experimental cohort, That vibrations similar to these stimulated an increase in bone density and strength in humans, and that skeletal loading is an inevitable product of functional load bearing, we believe that vibration energy can represent not only a preventive approach but also a therapy for osteoporosis. For that, larger population scale studies must be performed in order to verify the effectiveness of vibration treatments and its combination with exercise regimen on the spine and the lower limbs to prevent bone loss falls and related bone fractures in elderly people.